Year 10 Chemistry - Semster Exam Revision

Three subatomic particles?

Protons, neutrons, electrons

Atomic number?

Number of protons

Where electrons are found?

In shells around nucleus

Charges of proton, neutron, electron

+1, 0, -1

How metals form ions?

Lose electrons, become cations

How non-metals form ions?

Gain electrons - become anions

Group 1 ion charge?

+1

Group 2 ion charge?

+2

Group 3 ion charge?

+3

Group 5 ion charge?

-3

Group 6 ion charge?

-2

Group 7 ion charge?

-1

What do groups show?

Number of valence electrons

What do periods show?

Number of electron shells

Properties of metals?

Malleable, ductile, shiny, conduct heat/electricity

Properties of non-metals?

Brittle, dull, poor conductors

Group 1 name?

Alkali metals

Group 2 name?

Alkaline earth metals

Group 7 name?

Halogens

Group 8 name?

Noble gases

Ionic bonding

Transfer of electrons from metal to non-metal

Structure of ionic compounds?

Giant lattice of positive and negative ions

Covalent bonding?

Sharing of electrons between non-metals

Properties of covalent molecular substances?

Low melting/boiling points, no conductivity

Metallic bonding?

Lattice of positive ions with delocalised electrons

Cross over steps

Write ions - cross charges - drop signs - simplify - brackets if needed

When do you use brackets in formulas?

When a polyatomic ion has a subscript >1

Always soluble ions

Group 1

Insoluble carbonates

Except Group 1

Insoluble hydroxides

Except Group 1

What is a precipitate?

Insoluble solid formed in solution

Identifying a precipitate?

Use solubility rules

Collision theory

Particles must collide with enough energy and correct orientation

How does temperature affect rate?

Higher temp, faster particles, more collisions

How does concentration affect rate?

More particles, more collisions

How does surface area affect rate?

More exposed area, more collisions

What does a catalyst do?

Lower activation energy, meaning faster reaction